comment _getAllVariableMirror()
add Document
add validation() to Document
add mongo_dart as dependency
initial commit of collection and mongodb
add validate(), save(), delete(), and _clone() to Document
add document_test.dart
add document_test.dart as dependency
handle how Collection assigning value to ObjectId
fix error where we use mirror instead of reflectedType
adding default value to minLength and maxLength
no need to check if the args type is Document
add new TypeMatcher -> _IsDocument and _IsObjectId
add Document test (document_test.dart), right now only test how to save model to db
adding delete test to Document test
change how we add Field to validator, now if the validator is exist, we don't have to add a new one
minor refactoring